A new species of the water skink, of the genus Tropidophorus was described as T. hangnam, sp. nov, based on ten specimens collected from Phu Khiew Wildlife Sanctuary, Chaiyaphum Province, northeastern Thailand. This species is characterized by having the following characteristics: head scales smooth; dorsal weakly keeled, lateral body, and upper, anterior and posterior parts of limbs keeled; tail with strong spine-like keels in lateral; lateral scale-rows directed obliquely; two enlarge preanal scales; no subcaudal median scale rows; tail shorter than SVL. The record makes the species account in Thailand up to nine